Tigecycline: a new antimicrobial agent against multiresistant bacteria

Emilia Cercenado

Tigecycline (Tygacil®, Wyeth Pharmaceuticals) is a glycylcycline that is active against many aerobic and anaerobic Gram-positive and -negative microorganisms, atypical microorganisms and rapidly growing mycobacteria. It binds to the bacterial 30S ribosomal subunit and blocks entry of amino-acyl transfer RNA molecules into the A site. Tigecycline evades acquired efflux and target-mediated resistance to classic tetracyclines, but not chromosomal efflux in Proteeae and Pseudomonas aeruginosa. It is administered intravenously as a 100 mg dose, followed by 50 mg every 12 h. The Cmax is low but tissue penetration is good. Tigecycline is indicated for the treatment of skin and skin-structure infections and complicated intra-abdominal infections, and could be useful in infections due to multiresistant microorganisms such as methicillin-resistant Staphylococcus aureus, enterococci, extended-spectrum β-lactamase-producing Enterobacteriaceae and Acinetobacter spp.